Free Home school Science Curriculum  Experiment – How Pulleys and Levers Work

Free Home school Science Curriculum Experiment – How Pulleys and Levers Work

I never fail to add simple machines as a home school curriculum topic, as simple machines are interesting in addition as intriguing. Levers and pulleys are two types of simple machines that help to multiply force. They permit you to do more work with less force.

To understand what a lever is imagine a see-saw in the park. The plank that tilts from side to side is a lever, and the sustain in the center of the plank on which the plank pivots is the fulcrum. To understand what a pulley is imagine the wheel fixed over a well with a rope over it that helps to draw water from the well. A pulley is nothing but a wheel with a groove that turns on an axle.

Levers and pulleys help lift or pull heavy objects. The trick with levers and pulleys is that the farther you are from the fulcrum or the axle as compared to the heavy objects, the lesser the force you will require to lift or pull the object. I have tons of exciting experiments based on simple machines that could make your home school curriculum fun and easy.

With a lever you can lift a person three times your weight; only you will have to move three times away from the fulcrum as compared to the person’s distance from the fulcrum. For example, if you weigh 100 pounds, you can lift a 300 pound person who is standing 1 meter away from the fulcrum. You just have to stand 3 meters away from the fulcrum. Similarly, you can single-handily lift 5 people who are standing 10 feet away from the pulley by standing 50 feet away. Aren’t you amazed at the strength of levers and pulleys?

Before we move on to our exciting experiment you must understand what the term ‘mechanical advantage’ or ‘leverage’ method. Mechanical advantage is the maximum load you can lift with the same effort on your part. After the first experiment you will learn that the more the levers the more load you can lift with the same effort.

Now here’s my favorite home school curriculum experiment!

The Dowel Pulley Experiment: You will need two of your friends, two strong 18 inch dowels and a slippery nylon rope for this experiment. Have your friends stand facing each other with each friend grasping a dowel with both their hands at chest level. The dowels must be held horizontally, at the same height from the floor and similar to each other. Let the two dowels be at the minimum 2 feet apart.

Now tie one end of the nylon rope firmly to the dowel between the hands of one friend, seeing to it that you tie it as close to one hand as possible. Now pass the rope over the other dowel and pull it from under, bringing it over the first dowel. Wind the rope around both dowels in such a way that two complete loops are formed crisscrossing in the form of an ‘M.’ Now keep up the free end of the nylon rope firmly and ask both your friends to pull the dowels apart while you prevent them from doing it. Can they do it?

Now tug at the rope and ask your friends to resist your pull. Are the two of them strong enough to resist your tug at the rope?

Next, Wind the rope around both dowels in such a way that four complete loops are formed. Now repeat the tug of war. You will see that more the loops the easier it becomes for you to defeat your friends. What does this tell you about pulleys?

observe that the dowels act as pulleys. The more loops average more pulleys. The more pulleys average less effort you have to put in.

If you enjoyed this experiment, there are many more that you could ask your teacher to add to your home school curriculum. Fore more great science experiments and activities visit the free “Home school Parent’s Guide to Teaching Science” at the link below.

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